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Hot gas accretion fuels star formation faster than cold accretion in high-redshift galaxies

Kocjan, Zuzanna LU ; Cadiou, Corentin LU orcid ; Agertz, Oscar LU and Pontzen, Andrew (2024) In Monthly Notices of the Royal Astronomical Society 534(1). p.918-929
Abstract

We use high-resolution (35pc) hydrodynamical simulations of galaxy formation to investigate the relation between gas accretion and star formation in galaxies hosted by dark matter haloes of mass at. At high-redshift, cold-Accreted gas is expected to be readily available for star formation, while gas accreted in a hot mode is expected to require a longer time to cool down before being able to form stars. Contrary to these expectations, we find that the majority of cold-Accreted gas takes several hundred Myr longer to form stars than hot-Accreted gas after it reaches the inner circumgalactic medium (CGM). Approximately 10 per cent of the cold-Accreted gas flows rapidly through the inner CGM on to the galactic disc. The remaining 90 per... (More)

We use high-resolution (35pc) hydrodynamical simulations of galaxy formation to investigate the relation between gas accretion and star formation in galaxies hosted by dark matter haloes of mass at. At high-redshift, cold-Accreted gas is expected to be readily available for star formation, while gas accreted in a hot mode is expected to require a longer time to cool down before being able to form stars. Contrary to these expectations, we find that the majority of cold-Accreted gas takes several hundred Myr longer to form stars than hot-Accreted gas after it reaches the inner circumgalactic medium (CGM). Approximately 10 per cent of the cold-Accreted gas flows rapidly through the inner CGM on to the galactic disc. The remaining 90 per cent is trapped in a turbulent accretion region that extends up to per cent of the virial radius, from which it takes several hundred Myr for the gas to be transported to the star-forming disc. In contrast, most hot shock-heated gas avoids this 'slow track', and accretes directly from the CGM on to the disc where stars can form. We find that shock-heating of cold gas after accretion in the inner CGM and supernova-driven outflows contribute to, but do not fully explain, the delay in star formation. These processes combined slow down the delivery of cold-Accreted gas to the galactic disc and consequently limit the rate of star formation in Milky Way mass galaxies at.

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Please use this url to cite or link to this publication:
author
; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
accretion, accretion discs, galaxies: disc, galaxies: formation, galaxies: star formation
in
Monthly Notices of the Royal Astronomical Society
volume
534
issue
1
pages
12 pages
publisher
Oxford University Press
external identifiers
  • scopus:85205445102
ISSN
0035-8711
DOI
10.1093/mnras/stae2128
language
English
LU publication?
yes
id
2112b7d3-520c-4eef-95ce-06e8be978222
date added to LUP
2024-12-10 08:52:10
date last changed
2025-01-08 15:12:28
@article{2112b7d3-520c-4eef-95ce-06e8be978222,
  abstract     = {{<p>We use high-resolution (35pc) hydrodynamical simulations of galaxy formation to investigate the relation between gas accretion and star formation in galaxies hosted by dark matter haloes of mass at. At high-redshift, cold-Accreted gas is expected to be readily available for star formation, while gas accreted in a hot mode is expected to require a longer time to cool down before being able to form stars. Contrary to these expectations, we find that the majority of cold-Accreted gas takes several hundred Myr longer to form stars than hot-Accreted gas after it reaches the inner circumgalactic medium (CGM). Approximately 10 per cent of the cold-Accreted gas flows rapidly through the inner CGM on to the galactic disc. The remaining 90 per cent is trapped in a turbulent accretion region that extends up to per cent of the virial radius, from which it takes several hundred Myr for the gas to be transported to the star-forming disc. In contrast, most hot shock-heated gas avoids this 'slow track', and accretes directly from the CGM on to the disc where stars can form. We find that shock-heating of cold gas after accretion in the inner CGM and supernova-driven outflows contribute to, but do not fully explain, the delay in star formation. These processes combined slow down the delivery of cold-Accreted gas to the galactic disc and consequently limit the rate of star formation in Milky Way mass galaxies at.</p>}},
  author       = {{Kocjan, Zuzanna and Cadiou, Corentin and Agertz, Oscar and Pontzen, Andrew}},
  issn         = {{0035-8711}},
  keywords     = {{accretion, accretion discs; galaxies: disc; galaxies: formation; galaxies: star formation}},
  language     = {{eng}},
  month        = {{10}},
  number       = {{1}},
  pages        = {{918--929}},
  publisher    = {{Oxford University Press}},
  series       = {{Monthly Notices of the Royal Astronomical Society}},
  title        = {{Hot gas accretion fuels star formation faster than cold accretion in high-redshift galaxies}},
  url          = {{http://dx.doi.org/10.1093/mnras/stae2128}},
  doi          = {{10.1093/mnras/stae2128}},
  volume       = {{534}},
  year         = {{2024}},
}